1. Field of the Invention
The present invention relates to a roofing system for a building structure, and more particularly but not by way of limitation, to an improved roofing system positionable over an existing roof. In one aspect, the invention relates to a method for installing a roof system over a substantially flat existing roof structure to form a new roof system having a desired planar surface substantially independent of the planar surface of the existing roof structure.
2. Discussion of Prior Art
Numerous types of roof assemblies have heretofore been proposed for buildings in an effort to provide a watertight roof assembly, while at the same time enabling the roof assembly to expand and contract as changes in temperature are encountered. One particular type of roof assembly heretofore used is a substantially flat roof assembly referred to in the construction industry as a "built-up" roof. Generally such a roof assembly is formed of a plurality of sections which are interconnected and/or overcoated with asphaltic composition to provide a watertight seal. While such roof assemblies have met with general success, problems have nevertheless been encountered in that as the roof assembly ages, or the building settles, or as a result of construction errors the drainage slope of the roof assembly often results in water standing in pockets throughout the roof assembly. This standing water often results in deterioration of the roof assembly causing leaks and the like to occur.
In an effort to repair a substantially flat roof assembly which has been damaged by the elements, or developed leaks therein, problems have been encountered in repairing the roof assembly in a satisfactory manner to prevent similar occurrences from happening. Thus, a need has long been recognized for a roof assembly for substantially reroofing a building which does not require substantial modifications to the existing roof assembly and which is economically both in fabrication and construction. Further, it is highly desirable that the new roof assembly be capable of altering the planar surface of the roof assembly of the building independent of the variations in the planar surface of the existing roof assembly. Past repair methods especially those capable of altering the planar surface to improve the drainage characteristics of the building have required substantial destruction of the original roof thus exposing the building and its contents to damage by the elements during the reroofing process.